Fatal error: Could not check compatibility between Dompdf\Frame\FrameTreeList::getIterator(): Dompdf\Frame\FrameTreeIterator and IteratorAggregate::getIterator(): Traversable, because class Dompdf\Frame\FrameTreeIterator is not available in /home/handioas/www/wp-content/plugins/mphb-invoices/vendors/dompdf/src/Frame/FrameTreeList.php on line 31